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A Search for Radio Pulsars in Supernova Remnants Using FAST with One Pulsar Discovered

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Chinese Physics Letters 2024年第2期41卷 133-136页

作者：张振闫文明袁建平王娜白俊涛温志刚李保达解进涛赵德王榆斌翟楠楠 Xinjiang Astronomical observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Radio Astronomy and Technology(Chinese Academy of Sciences) Beijing 100101China Xinjiang Key Laboratory of Radio Astrophysics Urumqi 830011China College of Physics GuiZhou UniversityGuizhou 550025China Research Center for Intelligent Computing Platforms Zhejiang LaboratoryHangzhou 311100China School of Physical Science and Technology Xinjiang UniversityUrumqi 830046China School of Physics and Electronic Engineering Sichuan University of Science&EngineeringZigong 643000China

We report the results of a search for radio pulsars in five supernova remnants(SNRs)with the FAST *** observations were made using the 19-beam receiver in“snapshot”*** integration time for each pointing was 10 *** discovered a new pulsar,PSR J1845–0306,which has a spin period of 983.6 ms and a dispersion measure of 444.6±2.0 cm^(−3)·pc,in observations of SNR G29.6+*** judge the association between the pulsar and the SNR,further verification is *** also re-detected some known pulsars in the data from SNRs G29.6+0.1 and G29.7–*** pulsars were detected in the observations of the other three SNRs.

关键词： observations Pulsar pulsar

气候因子和人类活动对松辽流域植被叶面积指数动态的影响

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生态学报 2024年第5期44卷 2043-2056页

作者：马云飞何全军张月维石艳军李建平袁福香吉林省气象科学研究所长春130062 长白山气象与气候变化吉林省重点实验室长春130062 吉林省农业气象灾害风险评估与防控科技创新中心长春130062 广州气象卫星地面站广州510640

了解气候变化和人类活动对植被的影响对陆地生态系统可持续发展具有重要意义。基于月尺度MODIS LAI、气象等数据,采用基于像元的趋势及偏相关分析、时滞与累积效应分析和改进的残差分析等方法,评估松辽流域2001—2021年生长季植被叶面... 详细信息

了解气候变化和人类活动对植被的影响对陆地生态系统可持续发展具有重要意义。基于月尺度MODIS LAI、气象等数据,采用基于像元的趋势及偏相关分析、时滞与累积效应分析和改进的残差分析等方法,评估松辽流域2001—2021年生长季植被叶面积指数(LAI)动态,在顾及时滞与累积效应的情况下探究气候与人为驱动因素对植被的影响。结果表明:(1)松辽流域LAI总体呈“平原低,山地高”的空间分布格局。近21年植被LAI在波动中呈上升趋势,未来植被变化以持续改善为主,但内蒙古西部草原及大、小兴安岭局部地区仍存在退化风险。(2)LAI总体上与气温、降水呈正相关,相较气温植被生长对降水更敏感。LAI变化的时间效应随气候因子、覆被类型及植被分区的不同而发生变化。LAI对气温的主要时间效应为2个月滞后和0—1个月累积,而对降水主要为无显著滞后和1个月累积。(3)气候变化和人类活动的联合作用是影响松辽流域植被LAI动态的主要原因,两者对植被变化的贡献分别占41.7%和58.3%,同时考虑时滞和累积效应时,提升了气候因子对植被生长的解释度。

关键词：气候因子松辽流域时滞累积效应人类活动残差分析

Multidecadal Trends in Large-Scale Annual Mean SATa Based on CMIP5 Historical Simulations and Future Projections

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Engineering 2017年第1期3卷 136-143页

作者： nan Xing jianping Li Lanning wang College of Global Change and Earth System Science Beijing Normal University Belting 100875 China Belting Meteorological observatory Belting 100089 China Joint Center for Global Change Studies Beijing 100875 China

Based on observations and Coupled Model lntercomparison Project Phase 5 （CMIP5） results, multidecadal variations and trends in annual mean surface air temperature anomalies （SATa） at global, hemispheric, and hemispheric land and ocean scales in the past and under the future scenarios of two representative concentration pathways （RCPs） are analyzed. Fifteen models are selected based on their performances in capturing the temporal variability, long-term trend, multidecadal variations, and trends in global annual mean SATa. Observational data analysis shows that the multidecadal variations in annual mean SATa of the land and ocean in the northern hemisphere （NH） and of the ocean in the southern hemisphere （SH） are similar to those of the global mean, showing an increase during the 1900-1944 and 1971-2000 periods, and flattening or even cooling during the 1945-1970 and 2001-2013 periods. These observed characteristics are basically reproduced by the models. However, SATa over SH land show an increase during the 1945-1970 period, which differs from the other hemispheric scales, and this feature is not captured well by the models. For the recent hiatus period （2001-2013）, the projected trends of BCC-CSM1-1-m, CMCC-CM, GFDL-ESM2M, and NorESM1-ME at the global and hemispheric scales are closest to the observations based on RCP4.5 and RCP8.5 scenarios, suggesting that these four models have better projection capability in SATa. Because these four models are better at simulating and projecting the multidecadal trends of SATa, they are selected to analyze future SATa variations at the global and hemispheric scales during the 2006-2099 period. The selected multi-model ensemble （MME） projected trends in annual mean SATa for the globe, NH, and SH under RCP4.5 （RCP8.5） are 0.17 （0.29） ℃, 0.22 （0.36） ℃, and 0.11 （0.23） ℃-decade-1 in the 21st century, respectively. These values are significantly lower than the projections of CMIP5 MME without model selection.

关键词： Surface air temperature anomalies (SATa) Multidecadal trend Coupled Model lntercomparison Project Phase 5 (CMIPS) Projection

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酶解糖化滇黄精多糖的结构表征及其免疫活性

现代食品科技 2024年第4期40卷 104-112页

作者：黄俊源袁晚晴苏艺杨淑婷黎攀陈建萍杜冰华南农业大学食品学院广东广州510642 香港大学李嘉诚医学院中医药学院中国香港999077

该论文研究了酶解糖化下的滇黄精多糖结构和免疫活性,以探究酶解糖化下的黄精多糖结构特征及免疫活性的影响。结果表明,酶解糖化黄精多糖(SPKP)的多糖和还原糖含量分别为94.05%、4.1%。多糖结构分析表明,SPKP的红外光谱在1016~1147和931... 详细信息

该论文研究了酶解糖化下的滇黄精多糖结构和免疫活性,以探究酶解糖化下的黄精多糖结构特征及免疫活性的影响。结果表明,酶解糖化黄精多糖(SPKP)的多糖和还原糖含量分别为94.05%、4.1%。多糖结构分析表明,SPKP的红外光谱在1016~1147和931 cm-1处有吡喃糖特征吸收峰;单糖组成及摩尔比为阿拉伯糖:半乳糖:葡萄糖:甘露糖:果糖=0.032:0.117:0.419:0.048:0.383,重均分子量(Mw)为3820 u。甲基化结果表明SPKP主要的糖苷键连接方式为(→4-Glcp-1→),占比47.1%,分支度为34.1%结合碘碘化钾和刚果红实验结果可以推测SPKP是一种含有复杂分支的三股螺旋多糖。RAW264.7细胞实验结果表明,酶解糖化黄精多糖在比较广的浓度范围内无毒性,均能促进细胞增殖,且有较高的细胞吞噬能力和NO水平,因此可以推测SPKP具有较好的免疫活性,且与其多糖结构有一定的关系。该研究可以为多糖与免疫活性的构效关系以及黄精新炮制方法的开发提供一定参考。

关键词：滇黄精酶解糖化多糖结构免疫活性

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脉冲星J2313+4253的周期性消零和奇偶调制特性的研究

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中国科学：物理学、力学、天文学 2024年第4期54卷 185-198页

作者：陈建玲温志刚王洪光王娜袁建平 Rai Yuen 闫文明韩伟李永宏王金鹏项斌斌运城学院物理与电子工程系运城044000 中国科学院新疆天文台乌鲁木齐830011 广州大学天体物理中心广州510006 新疆大学机电工程学院乌鲁木齐830017

脉冲星子脉冲的强度调制特征对揭示脉冲星辐射过程和磁层几何具有重要意义.前人研究表明,PSR J2313+4253的单脉冲序列具有44倍和2倍自转周期的强度调制.其中2倍周期的调制周期被称为奇偶性调制,其物理起源并不清晰.本文利用佳木斯66 m... 详细信息

脉冲星子脉冲的强度调制特征对揭示脉冲星辐射过程和磁层几何具有重要意义.前人研究表明,PSR J2313+4253的单脉冲序列具有44倍和2倍自转周期的强度调制.其中2倍周期的调制周期被称为奇偶性调制,其物理起源并不清晰.本文利用佳木斯66 m射电望远镜的观测数据,对脉冲星J2313+4253在2250 MHz的单脉冲辐射特性进行了详细研究.通过相位分离涨落谱(LRFS)、谐频分离的涨落谱(HRFS)和二维涨落谱(2DFS)的分析方法,发现PSR J2313+4253的奇偶性调制来自于其短周期子脉冲漂移,并且调制现象展现出了时间依赖性.分析表明,旋转木马模型下,奇偶性调制可能起源于脉冲星火花放电过程中,辐射区子辐射束间边界不清晰而发生的混叠效应.

关键词：脉冲星单脉冲消零

Discharge characteristics and reactive species production of unipolar and bipolar nanosecond pulsed gas–liquid discharge generated in atmospheric N2

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Plasma Science and Technology 2021年第9期23卷 123-134页

作者： jianping LIANG Xiongfeng ZHOU Zilu ZHAO Hao yuan Hongli wang Wenchun wang Dezheng YANG Key Lab of Materials Modification(Dalian University of Technology) Ministry of EducationDalian 116024People's Republic of China

In this paper,unipolar pulse(including positive pulse and negative pulse)and bipolar pulse voltage are employed to generate diffuse gas–liquid discharge in atmospheric N2with a rumpetshaped quartz *** current–voltage waveforms,optical emission spectra of excited state active species,FTIR spectra of exhaust gas components,plasma gas temperature,and aqueous H2O2,NO2-,andNO3-production are compared in three pulse modes,meanwhile,the effects of pulse peak voltage and gas flow rate on the production of reactive species are *** results show that two obvious discharges occur in each voltage pulse in unipolar pulse driven discharge,differently,in bipolar pulse driven discharge,only one main discharge appears in a single voltage pulse *** intensities of active species(OH(A),and O(3p))in all three pulsed discharge increase with the rise of pulse peak voltage and have the highest value at 200 ml min-1of gas flow *** absorbance intensities of NO2and N2O increase with the increase of pulse peak voltage and decrease with the increase of gas flow *** the same discharge conditions,the bipolar pulse driven discharge shows lower breakdown voltage,and higher intensities of excited species(N2(C),OH(A),and O(3p)),nitrogen oxides(NO2,NO,and N2O),and higher production of aqueous H2O2,NO2-,andNO3-compared with both unipolar positive and negative discharges.

关键词： nanosecond pulse discharge gas-liquid discharge optical emission spectra reactive species FTIR spectra

Noble metal aerogels rapidly synthesized by ultrasound for electrocatalytic reaction

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Chinese Chemical Letters 2022年第4期33卷 2021-2025页

作者： Yueyue yuan Huan Zhao Wenxia Xv Dan Zhang Zuochao wang Hongdong Li Yingnan Qin Shaoxiang Li jianping Lai Lei wang Key Laboratory of Eco-chemical Engineering Key Laboratory of Optic-electric Sensing and Analytical Chemistry of Life ScienceTaishan Scholar Advantage and Characteristic Discipline Team of Eco Chemical Process and TechnologyCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China Shandong Engineering Research Center for Marine Environment Corrosion and Safety Protection College of Environment and Safety EngineeringQingdao University of Science and TechnologyQingdao 266042China

Noble metal aerogels(NMAs), belonging to the porous material, have exhibited excellent catalytic performance. Although the synthesis method continues to improve, it still exists some problems which hindered the experimental process, such as high concentration of noble metal precursors, long synthesis cycle, expensive production cost, and uncontrollable ligament length. In this work, ultrasonic wave and reducing agent na BH;were simultaneously applied to gelation process. With the cavitation of ultrasound,it can generate huge energy with heating and stirring, thus gelation reaction proceeded quickly, and even completed the process in only a few seconds, that is much faster than the recorded. A wide concentration range was successfully expanded from 0.02 mmol/L to 62.5 mmol/L. Further, we extended this method to a variety of noble metal elements(Au, Ru, Rh, Ag, Pt, Pd), and this method is adaptive for the synthesis of single metal aerogels(Au, Ag, Ru, Rh, Pd), bimetal and trimetal aerogels(Au-Ag, Au-Rh, Au-Ru, Au-Pt,Au-Pd, Au-Pt-Pd). In addition, the ligament size of alloy aerogels are 10 nm or less. Moreover, their brilliant properties were demonstrated in hydrogen evolution reaction(HER) and ethanol oxidation reaction(EOR).

关键词： Ultrasonic Aerogels Noble metals Rapid synthesis Electrocatalysis

不同土壤管理方式对南疆芽变香梨优系土壤养分及酶活性的影响

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北方园艺 2024年第18期 72-83页

作者：郭松超庄元郭凯璐余明杨包建平陈强塔里木大学园艺与林学学院南疆特色果树高效优质栽培与深加工技术国家地方联合工程实验室新疆阿拉尔843300

以芽变香梨优系为试材,设置了CK(无覆盖)、T1(地布覆盖)、T2(生草覆盖)、T3(菌肥)、T4(有机肥)、T5(有机肥+菌肥)6种农艺处理,研究了不同田间管理方式对土壤养分及酶活性的影响,以期为解决芽变香梨优系在栽培过程中土壤管理提供参考依... 详细信息

以芽变香梨优系为试材,设置了CK(无覆盖)、T1(地布覆盖)、T2(生草覆盖)、T3(菌肥)、T4(有机肥)、T5(有机肥+菌肥)6种农艺处理,研究了不同田间管理方式对土壤养分及酶活性的影响,以期为解决芽变香梨优系在栽培过程中土壤管理提供参考依据。结果表明:较CK,T1~T5处理浅层碱解氮、有效磷全氮、全磷、有机质含量均有显著提高;T3~T5处理速效钾含量较CK提高显著;对比CK,施用T1~T5措施处理均可以提高土壤脲酶、过氧化氢酶活性;T1~T5处理提高深层土壤养分含量、酶活性的效果随处理时间延长不断增强;综合分析,增加地面覆盖部分T2处理改良果园土壤效果更优,增施肥部分T5处理提高果园养分作用显著。建议梨园地面覆盖措施选用生草覆盖并定期施用菌肥、有机肥。

关键词：田间管理土壤养分酶活性

THE METHYLATION STATUS OF THE CPG ISLAND IN THE PROMOTER OF FOXA2 DURING CELLULAR SENESCENCE OF HUMAN EMBRYONIC LUNG FIBROBLASTS

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THE METHYLATION STATUS OF THE CPG ISLAND IN THE PROMOTER OF ...